The guy makes his living as a writer. You think he doesn't understand sarcasm?
I don't think he understands alot of things, among them an awareness of professional reputation boundaries or a real keen understanding of how the real world operates.
I actually would be somewhat surprised if Rivals has not been in contact.
All journalistic integrity aside, most major organizations with any degree whatsoever of public relations and risk management view no distinction from professional and personal social media content and clearly outline policy for acceptable usage. And typically do not take lightly any content that embarrasses the company, reflects a lack of professionalism or diminishes the reputation of the brand.